blob: 0c7010526655ea538393e1fda934c08cd371a153 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
|
A non-structural-match type was used as the type of a const generic parameter.
Erroneous code example:
```compile_fail,E0741
#![feature(adt_const_params)]
struct A;
struct B<const X: A>; // error!
```
Only structural-match types, which are types that derive `PartialEq` and `Eq`
and implement `ConstParamTy`, may be used as the types of const generic
parameters.
To fix the previous code example, we derive `PartialEq`, `Eq`, and
`ConstParamTy`:
```
#![feature(adt_const_params)]
use std::marker::ConstParamTy;
#[derive(PartialEq, Eq, ConstParamTy)] // We derive both traits here.
struct A;
struct B<const X: A>; // ok!
```
|
